1. Field of the Invention
The present invention relates to vehicle sun visors that have a support rod for mounting to a vehicle cabin ceiling. The vehicle sun visors also have a visor body pivotally mounted to a horizontal rod portion of the support rod so that the visor body can pivot about an axis of the horizontal rod portion. The present invention also relates to methods for manufacturing such vehicle sun visors.
2. Description of the Related Art
A known sun visor may have a removal prevention projection formed on a part of the outer circumferential surface of a horizontal rod portion of a support rod so that a sun visor body may be prevented from being removed from the horizontal rod portion.
The support rod may be made of synthetic resin and the removal prevention projection may be integrally formed with the support rod so that the removal prevention projection is made of the same synthetic resin as the support rod. However, if a large force is applied to the visor body in a removing direction away from the support rod, there is a possibility that the removal prevention projection (made of synthetic resin) may be broken, allowing for the accidental removal of the visor body.
Therefore, Japanese Laid-Open Patent Publication No. 2002-301932 has proposed to reinforce the removal prevention projection by a reinforcing member that is made of metal and is inserted into the removal prevention projection. According to this publication, in order to insert the reinforcing member into the removal prevention projection, the reinforcing member is first set into a mold for the support rod. The molten synthetic resin may then be charged into the mold so that the support rod is molded with the reinforcing member inserted into the removal prevention projection.
There has also been known a method to insert a metal pipe into a support rod along the entire length of the support rod. Such a support rod may be used in conjunction with a visor body having an electric appliance, such as a dressing mirror unit with an illumination lamp, in order to supply electric power to the electric appliance. Thus, an electric cable may extend from an external power source to the electric appliance through the metal pipe. However, inserting the metal pipe into the support rod and wiring the electric cable through the metal pipe requires many troublesome operations and may increase the overall manufacturing cost.
Therefore, U.S. Pat. No. 5,143,678 has proposed to insert the electric cable through an insert molding process in which the electric cable is inserted into the support rod prior to the molding process for molding the support rod with a synthetic resin.
The above teachings may be used for reinforcing a removal prevention projection of a support rod with a metal reinforcing member and also for supplying power to an electric appliance of a visor body via an electric cable extending through the support rod. Thus, the metal reinforcing member and the electric cable may be set into a mold for the support rod. A molten synthetic resin may then be charged into the mold. As a result, the metal reinforcing member may be inserted into the removal prevention projection and the electric cable may be inserted into the support rod along the length of the support rod.
However, it is difficult to reliably set the metal reinforcing member and the electric cable to suitable positions within the mold. In addition, it is likely that the metal reinforcing member and the electric cable may be offset from their intended set positions. This could be due to the pressure of the flow of the molten synthetic resin that is charged into the mold during the molding process.